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              <strong>What priorities should threads/tasks executing Berkeley DB functions
be given?</strong>
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            <p>Tasks executing Berkeley DB functions should have the same, or roughly
equivalent, system priorities.  For example, it can be dangerous to give
tasks of control performing checkpoints a lower priority than tasks of
control doing database lookups, and starvation can sometimes result.</p>
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              <strong>Why isn't the C++ API exception safe?</strong>
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            <p>The Berkeley DB C++ API is a thin wrapper around the C API that maps most
return values to exceptions, and gives the C++ handles the same
lifecycles as their C counterparts.  One consequence is that if an
exception occurs while a cursor or transaction handle is open, the
application must explicitly close the cursor or abort the transaction.</p>
            <p>Applications can be simplified and bugs avoided by creating wrapper
classes around <a href="../api_reference/C/dbc.html" class="olink">DBC</a> and <a href="../api_reference/C/txn.html" class="olink">TXN</a> that call the appropriate
cleanup method in the wrapper's destructor.  By creating an instance
of the wrappers on the stack, C++ scoping rules will ensure that the
destructor is called before exception handling unrolls the block that
contains the wrapper object.</p>
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